csirt@kutim:~/threat-intel/cve/CVE-2026-89651

Katalog CVE

CVSS 9.8 · Critical EPSS 0,64%

Skor CVSS 3.1 9.8 (Critical) menurut CNA.

Deskripsi (NVD)

In the Linux kernel, the following vulnerability has been resolved: ceph: bound MDSCapAuth path and fs_name decode in handle_session() handle_session() decodes the MDSCapAuth records carried by a CEPH_SESSION_OPEN message (msg_version >= 6). For each record the match.path and match.fs_name byte strings are read by first decoding a 32-bit length and then copying that many bytes with the bare ceph_decode_copy(). Unlike the surrounding fields, which all use the _safe decode variants, these two copies are not preceded by a ceph_decode_need() bounds check, and the enclosing MDSCapAuth and MDSCapMatch struct_len fields are skipped rather than enforced as an upper bound. A length larger than the bytes remaining in the message front makes ceph_decode_copy() read past the end of the front buffer. The message front is a dedicated allocation (ceph_msg_new2() -> kvmalloc), so the over-read runs off that object. A malicious or compromised MDS can trigger this with the first post-connect message on mount, with no client-side user interaction; under KASAN it is reported as a slab-out-of-bounds read in handle_session(). Impact: a malicious MDS can force the kernel client to read up to 4 GiB past the message front allocation during session setup, crashing the client (out-of-bounds read). Switch both copies to ceph_decode_copy_safe(), which performs the ceph_decode_need() bounds check before the copy and branches to the existing bad label, matching the rest of the decoder and the error path that frees the partially decoded cap_auths array.

Rincian

Terbit di NVD
11 September 2026
Terakhir diubah
13 September 2026
Status NVD
Received
CVSS 3.1
9.8 (Critical), sumber CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H · uraikan di kalkulator
EPSS (30 hari)
0,64% peluang dieksploitasi; lebih tinggi dari 49,0% CVE lain

Produk dan versi terdampak

NVD belum mencantumkan data produk (CPE) untuk CVE ini. Produk yang terdampak biasanya disebut di deskripsi dan di advisory vendor pada daftar referensi.

Referensi dan perbaikan

Sumber: NVD · CVE.org · EPSS. Halaman ini disusun otomatis dari data tersebut; pembaruan terakhir 5 Okt 2026, 20:11 WITA. Kalau sistem di Perangkat Daerah memakai produk ini dan butuh bantuan, laporkan lewat kanal pelaporan.